It is known to use welding bugs in automated pipe welding arrangements. In such arrangements, at least two welding bugs are typically mounted, on a pipe clamp, for circumferential movement around the pipe so that torches on the bugs may weld within a groove defined between the pipes. It may be necessary, in some circumstances, to disengage at least part of that bug (by moving it). For example, the torch may be disengaged so as not to obstruct another welding bug performing its weld pass.
Typically the movement to a disengaged position includes lifting the torch out from the groove and then rotating the welding torch on the bug to one side, by rotating the torch about an axis that extends vertically relative to the welding bug (i.e. parallel to its height and typically radially when the bug is mounted on a pipe). However, moving the welding torches to such a position tends to make the welding bug cumbersome on the pipe. The welding bug may take up a relatively large amount of space on the pipe circumference and be difficult to manoeuvre. In addition, this arrangement on a welding bug may be heavy and/or difficult to maintain.
A possible solution to the problem is to move to the disengaged position by lifting the torch from the groove and then moving the main body of the bug backwards. However, this may be undesirable since the cutback of the pipe coating (for example a concrete coating) may need to be extended. This may be expensive, and in some cases, not be feasible.